PCNS - Low runtime shutdown, service and failure to reboot

[BillP]

Hello.

I've recently started using an AP9617 in one of our SUA3000s.

I have PCNS installed on two servers, the idea being that they then run a script to remotely shut down all the other servers (shutdown -m etc etc) - they both attempt to shut down everything for redundancy purposes - I have a shutdown event configured on them for "On Battery" with a delay of 60sec, and a cmd file configured within "Configure shutdown" with 30 seconds allowed to run.

These two servers are then supposed to restart once power is restored with a 5 minute delay. I have attempted to do this by setting the "Return delay" on the mgmt card to 300 seconds.

***

Two nights ago a power event occurred. According to the log, a low battery condition occurred 14 seconds later which immediately signalled a shutdown. The script to gracefully shutdown all servers failed. Although the UPS restarted after approximately 300 seconds, the servers did not.

***

So, my questions:
1) How do I stop a shutdown occurring on a "low battery" condition, OR how do I prevent a low battery condition from occurring so quickly? (I am NOT going to reduce the load, please don't bother suggesting it)

2) Why did my script fail? This same script worked fine with PCBE. My guess is that it was because the PCNS service (PowerChute Network Shutdown Group 1?) was running as local system which of course doesn't have authority to shutdown other machines? Is there anything else?

3) Why didn't the 2 servers restart when power was restored? Do I need to configure this within BIOS?

Thanks
//Rob

[BillP]

bump

Really can't have the PDC and SDC shutting themselves down because of a 14 second powercut.

Any more ideas or does anyone from APC have anything to say?

This is an SUA3000RM with half load.

Thanks.

[EZ_Button_apc]

Low battery is a default shutdown setting. It's actually configured on the Network Management Card, not PCNS. It's the configuration for Low Battery Duration... in other words, how much time is left before the UPS shuts off. The default is 2 minutes, but that can be increased. You don't have to do anything configuration wise for PCNS to shutdown at low battery, just look at the shutdown settings portion of PCNS.

You're probably dead on as to why the script didn't work. Not having the correct access will cause this and is a common problem.

You're right about the bios as well. APC's software is designed to shutdown the server and put the UPS into sleep mode. When power restores, the UPS turns back on and provides power to the outlets. You need to configure in the systems bios settings to turn on when power is present.

[BillP]

Thanks EZ.

I think you've answered questions 2 and 3 there. Unfortunately I can't test them without taking down our PDC, but time will tell!

The low battery duration however:

If I increase the low battery duration, my understanding is that I am increasing the time the UPS believes is required for its equipment to shutdown properly, which would cause it to start shutdown as soon as power fails. Indeed, if I increase it to 27 minutes (currently on 2 mins), its status changes to "batteries discharged".

More ideas please?

[EZ_Button_apc]

Hmm I think I didn't read that properly the first time when you asked "how do I stop the low battery shutdown."

You can't disable low battery shutdown, it's there as a safety buffer.

What do you have for runtime on the unit? With half load, you certainly should have more than 17 seconds before low battery occurs, so that tells me there is a problem somewhere.

Message was edited by: EZ Button

[BillP · Accepted solution]

"Safety buffer"? I thought the idea of having a managed system was that -you- configure how it works, not some piece of software that believes itself to be cleverer than you? My 2C 🙂

Anyway.
Reports 5 minutes of runtime, which is actually achieved aswell in a power failure - I've timed it.
UPS was also calibrated fully 2 months ago.
Batteries are a little old - 2005, but 5 minutes is sufficient to shutdown the equipment with a 60 sec delay so I see no reason to replace them yet.

I've opened this as a call with APC, but still any ideas welcomed - I'm expecting them to tell me to reduce the load or replace the battery...